package b面向对象.day4.demo5_protected.tst;

import b面向对象.day4.demo5_protected.A;

public class Test{
    public static void main(String[] args) {
        A a=new A();
//        a.m=30;
//        new Test().m=30;

        B b=new B();
//        b.m=550;
    }
}
